// Emacs style mode select	 -*- C++ -*-
//-----------------------------------------------------------------------------
//
// $Id:$
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// This source is available for distribution and/or modification
// only under the terms of the DOOM Source Code License as
// published by id Software. All rights reserved.
//
// The source is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code License
// for more details.
//
//
// $Log:$
//
// DESCRIPTION:	 the automap code
//
//-----------------------------------------------------------------------------

static const char rcsid[] = "$Id: am_map.c,v 1.4 1997/02/03 21:24:33 b1 Exp $";

#include <stdio.h>


#include "z_zone.h"
#include "doomdef.h"
#include "st_stuff.h"
#include "p_local.h"
#include "w_wad.h"

#include "m_cheat.h"
#include "i_system.h"

// Needs access to LFB.
#include "v_video.h"

// State.
#include "doomstat.h"
#include "r_state.h"

// Data.
#include "dstrings.h"

#include "am_map.h"


// For use if I do walls with outsides/insides
#define REDS			(256-5*16)
#define REDRANGE		16
#define BLUES			(256-4*16+8)
#define BLUERANGE		8
#define GREENS			(7*16)
#define GREENRANGE		16
#define GRAYS			(6*16)
#define GRAYSRANGE		16
#define BROWNS			(4*16)
#define BROWNRANGE		16
#define YELLOWS			(256-32+7)
#define YELLOWRANGE		1
#define BLACK			0
#define WHITE			(256-47)

// Automap colors
#define BACKGROUND		BLACK
#define YOURCOLORS		WHITE
#define YOURRANGE		0
#define WALLCOLORS		REDS
#define WALLRANGE		REDRANGE
#define TSWALLCOLORS	GRAYS
#define TSWALLRANGE		GRAYSRANGE
#define FDWALLCOLORS	BROWNS
#define FDWALLRANGE		BROWNRANGE
#define CDWALLCOLORS	YELLOWS
#define CDWALLRANGE		YELLOWRANGE
#define THINGCOLORS		GREENS
#define THINGRANGE		GREENRANGE
#define SECRETWALLCOLORS WALLCOLORS
#define SECRETWALLRANGE WALLRANGE
#define GRIDCOLORS		(GRAYS + GRAYSRANGE/2)
#define GRIDRANGE		0
#define XHAIRCOLORS		GRAYS

// drawing stuff
#define FB				0

#define AM_PANDOWNKEY	KEY_DOWNARROW
#define AM_PANUPKEY		KEY_UPARROW
#define AM_PANRIGHTKEY	KEY_RIGHTARROW
#define AM_PANLEFTKEY	KEY_LEFTARROW
#define AM_ZOOMINKEY	'='
#define AM_ZOOMOUTKEY	'-'
#define AM_STARTKEY		KEY_TAB
#define AM_ENDKEY		KEY_TAB
#define AM_GOBIGKEY		'0'
#define AM_FOLLOWKEY	'f'
#define AM_GRIDKEY		'g'
#define AM_MARKKEY		'm'
#define AM_CLEARMARKKEY 'c'

#define AM_NUMMARKPOINTS 10

// scale on entry
#define INITSCALEMTOF (.2*FRACUNIT)
// how much the automap moves window per tic in frame-buffer coordinates
// moves 140 pixels in 1 second
#define F_PANINC		4
// how much zoom-in per tic
// goes to 2x in 1 second
#define M_ZOOMIN		((int) (1.02*FRACUNIT))
// how much zoom-out per tic
// pulls out to 0.5x in 1 second
#define M_ZOOMOUT		((int) (FRACUNIT/1.02))

// translates between frame-buffer and map distances
#define FTOM(x) FixedMul(((x)<<16),scale_ftom)
#define MTOF(x) (FixedMul((x),scale_mtof)>>16)
// translates between frame-buffer and map coordinates
#define CXMTOF(x)  (f_x + MTOF((x)-m_x))
#define CYMTOF(y)  (f_y + (f_h - MTOF((y)-m_y)))

// the following is crap
#define LINE_NEVERSEE ML_DONTDRAW

typedef struct
{
    int x, y;
} fpoint_t;

typedef struct
{
    fpoint_t a, b;
} fline_t;

typedef struct
{
    fixed_t				x,y;
} mpoint_t;

typedef struct
{
    mpoint_t a, b;
} mline_t;

typedef struct
{
    fixed_t slp, islp;
} islope_t;



//
// The vector graphics for the automap.
//	A line drawing of the player pointing right,
//	 starting from the middle.
//
#define R ((8*PLAYERRADIUS)/7)
mline_t player_arrow[] = {
    { { -R+R/8, 0 }, { R, 0 } }, // -----
    { { R, 0 }, { R-R/2, R/4 } },  // ----->
    { { R, 0 }, { R-R/2, -R/4 } },
    { { -R+R/8, 0 }, { -R-R/8, R/4 } }, // >---->
    { { -R+R/8, 0 }, { -R-R/8, -R/4 } },
    { { -R+3*R/8, 0 }, { -R+R/8, R/4 } }, // >>--->
    { { -R+3*R/8, 0 }, { -R+R/8, -R/4 } }
};
#undef R
#define NUMPLYRLINES (sizeof(player_arrow)/sizeof(mline_t))

#define R ((8*PLAYERRADIUS)/7)
mline_t cheat_player_arrow[] = {
    { { -R+R/8, 0 }, { R, 0 } }, // -----
    { { R, 0 }, { R-R/2, R/6 } },  // ----->
    { { R, 0 }, { R-R/2, -R/6 } },
    { { -R+R/8, 0 }, { -R-R/8, R/6 } }, // >----->
    { { -R+R/8, 0 }, { -R-R/8, -R/6 } },
    { { -R+3*R/8, 0 }, { -R+R/8, R/6 } }, // >>----->
    { { -R+3*R/8, 0 }, { -R+R/8, -R/6 } },
    { { -R/2, 0 }, { -R/2, -R/6 } }, // >>-d--->
    { { -R/2, -R/6 }, { -R/2+R/6, -R/6 } },
    { { -R/2+R/6, -R/6 }, { -R/2+R/6, R/4 } },
    { { -R/6, 0 }, { -R/6, -R/6 } }, // >>-dd-->
    { { -R/6, -R/6 }, { 0, -R/6 } },
    { { 0, -R/6 }, { 0, R/4 } },
    { { R/6, R/4 }, { R/6, -R/7 } }, // >>-ddt->
    { { R/6, -R/7 }, { R/6+R/32, -R/7-R/32 } },
    { { R/6+R/32, -R/7-R/32 }, { R/6+R/10, -R/7 } }
};
#undef R
#define NUMCHEATPLYRLINES (sizeof(cheat_player_arrow)/sizeof(mline_t))

#define R (FRACUNIT)
mline_t triangle_guy[] = {
    { { -.867*R, -.5*R }, { .867*R, -.5*R } },
    { { .867*R, -.5*R } , { 0, R } },
    { { 0, R }, { -.867*R, -.5*R } }
};
#undef R
#define NUMTRIANGLEGUYLINES (sizeof(triangle_guy)/sizeof(mline_t))

#define R (FRACUNIT)
mline_t thintriangle_guy[] = {
    { { -.5*R, -.7*R }, { R, 0 } },
    { { R, 0 }, { -.5*R, .7*R } },
    { { -.5*R, .7*R }, { -.5*R, -.7*R } }
};
#undef R
#define NUMTHINTRIANGLEGUYLINES (sizeof(thintriangle_guy)/sizeof(mline_t))




static int		cheating = 0;	// XXX always cheating
static int		grid = 0;

static int		leveljuststarted = 1;	// kluge until AM_LevelInit() is called

boolean			automapactive = false;
static int		finit_width = SCREENWIDTH;
static int		finit_height = SCREENHEIGHT - 32;

// location of window on screen
static int		f_x;
static int		f_y;

// size of window on screen
static int		f_w;
static int		f_h;

static int		lightlev;				// used for funky strobing effect
static byte*	fb;						// pseudo-frame buffer
static int		amclock;

static mpoint_t m_paninc; // how far the window pans each tic (map coords)
static fixed_t	mtof_zoommul; // how far the window zooms in each tic (map coords)
static fixed_t	ftom_zoommul; // how far the window zooms in each tic (fb coords)

static fixed_t	m_x, m_y;	// LL x,y where the window is on the map (map coords)
static fixed_t	m_x2, m_y2; // UR x,y where the window is on the map (map coords)

//
// width/height of window on map (map coords)
//
static fixed_t	m_w;
static fixed_t	m_h;

// based on level size
static fixed_t	min_x;
static fixed_t	min_y;
static fixed_t	max_x;
static fixed_t	max_y;

static fixed_t	max_w; // max_x-min_x,
static fixed_t	max_h; // max_y-min_y

// based on player size
static fixed_t	min_w;
static fixed_t	min_h;


static fixed_t	min_scale_mtof; // used to tell when to stop zooming out
static fixed_t	max_scale_mtof; // used to tell when to stop zooming in

// old stuff for recovery later
static fixed_t old_m_w, old_m_h;
static fixed_t old_m_x, old_m_y;

// old location used by the Follower routine
static mpoint_t f_oldloc;

// used by MTOF to scale from map-to-frame-buffer coords
static fixed_t scale_mtof = INITSCALEMTOF;
// used by FTOM to scale from frame-buffer-to-map coords (=1/scale_mtof)
static fixed_t scale_ftom;

static player_t *plr; // the player represented by an arrow

static patch_t *marknums[10]; // numbers used for marking by the automap
static mpoint_t markpoints[AM_NUMMARKPOINTS]; // where the points are
static int markpointnum = 0; // next point to be assigned

static int followplayer = 1; // specifies whether to follow the player around

static unsigned char cheat_amap_seq[] = { 0xb2, 0x26, 0x26, 0x2e, 0xff };
static cheatseq_t cheat_amap = { cheat_amap_seq, 0 };

static boolean stopped = true;

extern boolean viewactive;
//extern byte screens[][SCREENWIDTH*SCREENHEIGHT];



void
V_MarkRect
( int	x,
  int	y,
  int	width,
  int	height );

// Calculates the slope and slope according to the x-axis of a line
// segment in map coordinates (with the upright y-axis n' all) so
// that it can be used with the brain-dead drawing stuff.

void
AM_getIslope
( mline_t*		ml,
  islope_t*		is )
{
    int dx, dy;

    dy = ml->a.y - ml->b.y;
    dx = ml->b.x - ml->a.x;
    if (!dy) is->islp = (dx<0?-MAXINT:MAXINT);
    else is->islp = FixedDiv(dx, dy);
    if (!dx) is->slp = (dy<0?-MAXINT:MAXINT);
    else is->slp = FixedDiv(dy, dx);

}

//
//
//
void AM_activateNewScale(void)
{
    m_x += m_w/2;
    m_y += m_h/2;
    m_w = FTOM(f_w);
    m_h = FTOM(f_h);
    m_x -= m_w/2;
    m_y -= m_h/2;
    m_x2 = m_x + m_w;
    m_y2 = m_y + m_h;
}

//
//
//
void AM_saveScaleAndLoc(void)
{
    old_m_x = m_x;
    old_m_y = m_y;
    old_m_w = m_w;
    old_m_h = m_h;
}

//
//
//
void AM_restoreScaleAndLoc(void)
{

    m_w = old_m_w;
    m_h = old_m_h;
    if (!followplayer)
    {
        m_x = old_m_x;
        m_y = old_m_y;
    } else {
        m_x = plr->mo->x - m_w/2;
        m_y = plr->mo->y - m_h/2;
    }
    m_x2 = m_x + m_w;
    m_y2 = m_y + m_h;

    // Change the scaling multipliers
    scale_mtof = FixedDiv(f_w<<FRACBITS, m_w);
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
}

//
// adds a marker at the current location
//
void AM_addMark(void)
{
    markpoints[markpointnum].x = m_x + m_w/2;
    markpoints[markpointnum].y = m_y + m_h/2;
    markpointnum = (markpointnum + 1) % AM_NUMMARKPOINTS;

}

//
// Determines bounding box of all vertices,
// sets global variables controlling zoom range.
//
void AM_findMinMaxBoundaries(void)
{
    int i;
    fixed_t a;
    fixed_t b;

    min_x = min_y =	 MAXINT;
    max_x = max_y = -MAXINT;

    for (i=0; i<numvertexes; i++)
    {
        if (vertexes[i].x < min_x)
            min_x = vertexes[i].x;
        else if (vertexes[i].x > max_x)
            max_x = vertexes[i].x;

        if (vertexes[i].y < min_y)
            min_y = vertexes[i].y;
        else if (vertexes[i].y > max_y)
            max_y = vertexes[i].y;
    }

    max_w = max_x - min_x;
    max_h = max_y - min_y;

    min_w = 2*PLAYERRADIUS; // const? never changed?
    min_h = 2*PLAYERRADIUS;

    a = FixedDiv(f_w<<FRACBITS, max_w);
    b = FixedDiv(f_h<<FRACBITS, max_h);

    min_scale_mtof = a < b ? a : b;
    max_scale_mtof = FixedDiv(f_h<<FRACBITS, 2*PLAYERRADIUS);

}


//
//
//
void AM_changeWindowLoc(void)
{
    if (m_paninc.x || m_paninc.y)
    {
        followplayer = 0;
        f_oldloc.x = MAXINT;
    }

    m_x += m_paninc.x;
    m_y += m_paninc.y;

    if (m_x + m_w/2 > max_x)
        m_x = max_x - m_w/2;
    else if (m_x + m_w/2 < min_x)
        m_x = min_x - m_w/2;

    if (m_y + m_h/2 > max_y)
        m_y = max_y - m_h/2;
    else if (m_y + m_h/2 < min_y)
        m_y = min_y - m_h/2;

    m_x2 = m_x + m_w;
    m_y2 = m_y + m_h;
}


//
//
//
void AM_initVariables(void)
{
    int pnum;
    static event_t st_notify = { ev_keyup, AM_MSGENTERED };

    automapactive = true;
    fb = screens[0];

    f_oldloc.x = MAXINT;
    amclock = 0;
    lightlev = 0;

    m_paninc.x = m_paninc.y = 0;
    ftom_zoommul = FRACUNIT;
    mtof_zoommul = FRACUNIT;

    m_w = FTOM(f_w);
    m_h = FTOM(f_h);

    // find player to center on initially
    if (!playeringame[pnum = consoleplayer])
        for (pnum=0; pnum<MAXPLAYERS; pnum++)
            if (playeringame[pnum])
                break;

    plr = &players[pnum];
    m_x = plr->mo->x - m_w/2;
    m_y = plr->mo->y - m_h/2;
    AM_changeWindowLoc();

    // for saving & restoring
    old_m_x = m_x;
    old_m_y = m_y;
    old_m_w = m_w;
    old_m_h = m_h;

    // inform the status bar of the change
    ST_Responder(&st_notify);

}

//
//
//
void AM_loadPics(void)
{
    int i;
    char namebuf[9];

    for (i=0; i<10; i++)
    {
        sprintf(namebuf, "AMMNUM%d", i);
        marknums[i] = W_CacheLumpName(namebuf, PU_STATIC);
    }

}

void AM_unloadPics(void)
{
    int i;

    for (i=0; i<10; i++)
        Z_ChangeTag(marknums[i], PU_CACHE);

}

void AM_clearMarks(void)
{
    int i;

    for (i=0; i<AM_NUMMARKPOINTS; i++)
        markpoints[i].x = -1; // means empty
    markpointnum = 0;
}

//
// should be called at the start of every level
// right now, i figure it out myself
//
void AM_LevelInit(void)
{
    leveljuststarted = 0;

    f_x = f_y = 0;
    f_w = finit_width;
    f_h = finit_height;

    AM_clearMarks();

    AM_findMinMaxBoundaries();
    scale_mtof = FixedDiv(min_scale_mtof, (int) (0.7*FRACUNIT));
    if (scale_mtof > max_scale_mtof)
        scale_mtof = min_scale_mtof;
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
}




//
//
//
void AM_Stop (void)
{
    static event_t st_notify = { 0, ev_keyup, AM_MSGEXITED };

    AM_unloadPics();
    automapactive = false;
    ST_Responder(&st_notify);
    stopped = true;
}

//
//
//
void AM_Start (void)
{
    static int lastlevel = -1, lastepisode = -1;

    if (!stopped) AM_Stop();
    stopped = false;
    if (lastlevel != gamemap || lastepisode != gameepisode)
    {
        AM_LevelInit();
        lastlevel = gamemap;
        lastepisode = gameepisode;
    }
    AM_initVariables();
    AM_loadPics();
}

//
// set the window scale to the maximum size
//
void AM_minOutWindowScale(void)
{
    scale_mtof = min_scale_mtof;
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
    AM_activateNewScale();
}

//
// set the window scale to the minimum size
//
void AM_maxOutWindowScale(void)
{
    scale_mtof = max_scale_mtof;
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
    AM_activateNewScale();
}


//
// Handle events (user inputs) in automap mode
//
boolean
AM_Responder
( event_t*		ev )
{

    int rc;
    static int cheatstate=0;
    static int bigstate=0;
    static char buffer[20];

    rc = false;

    if (!automapactive)
    {
        if (ev->type == ev_keydown && ev->data1 == AM_STARTKEY)
        {
            AM_Start ();
            viewactive = false;
            rc = true;
        }
    }

    else if (ev->type == ev_keydown)
    {

        rc = true;
        switch(ev->data1)
        {
            case AM_PANRIGHTKEY: // pan right
                if (!followplayer) m_paninc.x = FTOM(F_PANINC);
                else rc = false;
                break;
            case AM_PANLEFTKEY: // pan left
                if (!followplayer) m_paninc.x = -FTOM(F_PANINC);
                else rc = false;
                break;
            case AM_PANUPKEY: // pan up
                if (!followplayer) m_paninc.y = FTOM(F_PANINC);
                else rc = false;
                break;
            case AM_PANDOWNKEY: // pan down
                if (!followplayer) m_paninc.y = -FTOM(F_PANINC);
                else rc = false;
                break;
            case AM_ZOOMOUTKEY: // zoom out
                mtof_zoommul = M_ZOOMOUT;
                ftom_zoommul = M_ZOOMIN;
                break;
            case AM_ZOOMINKEY: // zoom in
                mtof_zoommul = M_ZOOMIN;
                ftom_zoommul = M_ZOOMOUT;
                break;
            case AM_ENDKEY:
                bigstate = 0;
                viewactive = true;
                AM_Stop ();
                break;
            case AM_GOBIGKEY:
                bigstate = !bigstate;
                if (bigstate)
                {
                    AM_saveScaleAndLoc();
                    AM_minOutWindowScale();
                }
                else AM_restoreScaleAndLoc();
                break;
            case AM_FOLLOWKEY:
                followplayer = !followplayer;
                f_oldloc.x = MAXINT;
                plr->message = followplayer ? AMSTR_FOLLOWON : AMSTR_FOLLOWOFF;
                break;
            case AM_GRIDKEY:
                grid = !grid;
                plr->message = grid ? AMSTR_GRIDON : AMSTR_GRIDOFF;
                break;
            case AM_MARKKEY:
                sprintf(buffer, "%s %d", AMSTR_MARKEDSPOT, markpointnum);
                plr->message = buffer;
                AM_addMark();
                break;
            case AM_CLEARMARKKEY:
                AM_clearMarks();
                plr->message = AMSTR_MARKSCLEARED;
                break;
            default:
                cheatstate=0;
                rc = false;
        }
        if (!deathmatch && cht_CheckCheat(&cheat_amap, ev->data1))
        {
            rc = false;
            cheating = (cheating+1) % 3;
        }
    }

    else if (ev->type == ev_keyup)
    {
        rc = false;
        switch (ev->data1)
        {
            case AM_PANRIGHTKEY:
                if (!followplayer) m_paninc.x = 0;
                break;
            case AM_PANLEFTKEY:
                if (!followplayer) m_paninc.x = 0;
                break;
            case AM_PANUPKEY:
                if (!followplayer) m_paninc.y = 0;
                break;
            case AM_PANDOWNKEY:
                if (!followplayer) m_paninc.y = 0;
                break;
            case AM_ZOOMOUTKEY:
            case AM_ZOOMINKEY:
                mtof_zoommul = FRACUNIT;
                ftom_zoommul = FRACUNIT;
                break;
        }
    }

    return rc;

}


//
// Zooming
//
void AM_changeWindowScale(void)
{

    // Change the scaling multipliers
    scale_mtof = FixedMul(scale_mtof, mtof_zoommul);
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);

    if (scale_mtof < min_scale_mtof)
        AM_minOutWindowScale();
    else if (scale_mtof > max_scale_mtof)
        AM_maxOutWindowScale();
    else
        AM_activateNewScale();
}


//
//
//
void AM_doFollowPlayer(void)
{

    if (f_oldloc.x != plr->mo->x || f_oldloc.y != plr->mo->y)
    {
        m_x = FTOM(MTOF(plr->mo->x)) - m_w/2;
        m_y = FTOM(MTOF(plr->mo->y)) - m_h/2;
        m_x2 = m_x + m_w;
        m_y2 = m_y + m_h;
        f_oldloc.x = plr->mo->x;
        f_oldloc.y = plr->mo->y;

        //	m_x = FTOM(MTOF(plr->mo->x - m_w/2));
        //	m_y = FTOM(MTOF(plr->mo->y - m_h/2));
        //	m_x = plr->mo->x - m_w/2;
        //	m_y = plr->mo->y - m_h/2;

    }

}

//
//
//
void AM_updateLightLev(void)
{
    static nexttic = 0;
    //static int litelevels[] = { 0, 3, 5, 6, 6, 7, 7, 7 };
    static int litelevels[] = { 0, 4, 7, 10, 12, 14, 15, 15 };
    static int litelevelscnt = 0;

    // Change light level
    if (amclock>nexttic)
    {
        lightlev = litelevels[litelevelscnt++];
        if (litelevelscnt == sizeof(litelevels)/sizeof(int)) litelevelscnt = 0;
        nexttic = amclock + 6 - (amclock % 6);
    }

}


//
// Updates on Game Tick
//
void AM_Ticker (void)
{

    if (!automapactive)
        return;

    amclock++;

    if (followplayer)
        AM_doFollowPlayer();

    // Change the zoom if necessary
    if (ftom_zoommul != FRACUNIT)
        AM_changeWindowScale();

    // Change x,y location
    if (m_paninc.x || m_paninc.y)
        AM_changeWindowLoc();

    // Update light level
    // AM_updateLightLev();

}


//
// Clear automap frame buffer.
//
void AM_clearFB(int color)
{
    memset(fb, color, f_w*f_h);
}


//
// Automap clipping of lines.
//
// Based on Cohen-Sutherland clipping algorithm but with a slightly
// faster reject and precalculated slopes.	If the speed is needed,
// use a hash algorithm to handle  the common cases.
//
boolean
AM_clipMline
( mline_t*		ml,
  fline_t*		fl )
{
    enum
    {
        LEFT	=1,
        RIGHT	=2,
        BOTTOM	=4,
        TOP		=8
    };

    register	outcode1 = 0;
    register	outcode2 = 0;
    register	outside;

    fpoint_t	tmp;
    int			dx;
    int			dy;


#define DOOUTCODE(oc, mx, my) \
	(oc) = 0; \
	if ((my) < 0) (oc) |= TOP; \
	else if ((my) >= f_h) (oc) |= BOTTOM; \
	if ((mx) < 0) (oc) |= LEFT; \
	else if ((mx) >= f_w) (oc) |= RIGHT;


    // do trivial rejects and outcodes
    if (ml->a.y > m_y2)
        outcode1 = TOP;
    else if (ml->a.y < m_y)
        outcode1 = BOTTOM;

    if (ml->b.y > m_y2)
        outcode2 = TOP;
    else if (ml->b.y < m_y)
        outcode2 = BOTTOM;

    if (outcode1 & outcode2)
        return false; // trivially outside

    if (ml->a.x < m_x)
        outcode1 |= LEFT;
    else if (ml->a.x > m_x2)
        outcode1 |= RIGHT;

    if (ml->b.x < m_x)
        outcode2 |= LEFT;
    else if (ml->b.x > m_x2)
        outcode2 |= RIGHT;

    if (outcode1 & outcode2)
        return false; // trivially outside

    // transform to frame-buffer coordinates.
    fl->a.x = CXMTOF(ml->a.x);
    fl->a.y = CYMTOF(ml->a.y);
    fl->b.x = CXMTOF(ml->b.x);
    fl->b.y = CYMTOF(ml->b.y);

    DOOUTCODE(outcode1, fl->a.x, fl->a.y);
    DOOUTCODE(outcode2, fl->b.x, fl->b.y);

    if (outcode1 & outcode2)
        return false;

    while (outcode1 | outcode2)
    {
        // may be partially inside box
        // find an outside point
        if (outcode1)
            outside = outcode1;
        else
            outside = outcode2;

        // clip to each side
        if (outside & TOP)
        {
            dy = fl->a.y - fl->b.y;
            dx = fl->b.x - fl->a.x;
            tmp.x = fl->a.x + (dx*(fl->a.y))/dy;
            tmp.y = 0;
        }
        else if (outside & BOTTOM)
        {
            dy = fl->a.y - fl->b.y;
            dx = fl->b.x - fl->a.x;
            tmp.x = fl->a.x + (dx*(fl->a.y-f_h))/dy;
            tmp.y = f_h-1;
        }
        else if (outside & RIGHT)
        {
            dy = fl->b.y - fl->a.y;
            dx = fl->b.x - fl->a.x;
            tmp.y = fl->a.y + (dy*(f_w-1 - fl->a.x))/dx;
            tmp.x = f_w-1;
        }
        else if (outside & LEFT)
        {
            dy = fl->b.y - fl->a.y;
            dx = fl->b.x - fl->a.x;
            tmp.y = fl->a.y + (dy*(-fl->a.x))/dx;
            tmp.x = 0;
        }

        if (outside == outcode1)
        {
            fl->a = tmp;
            DOOUTCODE(outcode1, fl->a.x, fl->a.y);
        }
        else
        {
            fl->b = tmp;
            DOOUTCODE(outcode2, fl->b.x, fl->b.y);
        }

        if (outcode1 & outcode2)
            return false; // trivially outside
    }

    return true;
}
#undef DOOUTCODE


//
// Classic Bresenham w/ whatever optimizations needed for speed
//
void
AM_drawFline
( fline_t*		fl,
  int			color )
{
    register int x;
    register int y;
    register int dx;
    register int dy;
    register int sx;
    register int sy;
    register int ax;
    register int ay;
    register int d;

    static fuck = 0;

    // For debugging only
    if (	  fl->a.x < 0 || fl->a.x >= f_w
              || fl->a.y < 0 || fl->a.y >= f_h
              || fl->b.x < 0 || fl->b.x >= f_w
              || fl->b.y < 0 || fl->b.y >= f_h)
    {
        fprintf(stderr, "fuck %d \r", fuck++);
        return;
    }

#define PUTDOT(xx,yy,cc) fb[(yy)*f_w+(xx)]=(cc)

    dx = fl->b.x - fl->a.x;
    ax = 2 * (dx<0 ? -dx : dx);
    sx = dx<0 ? -1 : 1;

    dy = fl->b.y - fl->a.y;
    ay = 2 * (dy<0 ? -dy : dy);
    sy = dy<0 ? -1 : 1;

    x = fl->a.x;
    y = fl->a.y;

    if (ax > ay)
    {
        d = ay - ax/2;
        while (1)
        {
            PUTDOT(x,y,color);
            if (x == fl->b.x) return;
            if (d>=0)
            {
                y += sy;
                d -= ax;
            }
            x += sx;
            d += ay;
        }
    }
    else
    {
        d = ax - ay/2;
        while (1)
        {
            PUTDOT(x, y, color);
            if (y == fl->b.y) return;
            if (d >= 0)
            {
                x += sx;
                d -= ay;
            }
            y += sy;
            d += ax;
        }
    }
}


//
// Clip lines, draw visible part sof lines.
//
void
AM_drawMline
( mline_t*		ml,
  int			color )
{
    static fline_t fl;

    if (AM_clipMline(ml, &fl))
        AM_drawFline(&fl, color); // draws it on frame buffer using fb coords
}



//
// Draws flat (floor/ceiling tile) aligned grid lines.
//
void AM_drawGrid(int color)
{
    fixed_t x, y;
    fixed_t start, end;
    mline_t ml;

    // Figure out start of vertical gridlines
    start = m_x;
    if ((start-bmaporgx)%(MAPBLOCKUNITS<<FRACBITS))
        start += (MAPBLOCKUNITS<<FRACBITS)
                 - ((start-bmaporgx)%(MAPBLOCKUNITS<<FRACBITS));
    end = m_x + m_w;

    // draw vertical gridlines
    ml.a.y = m_y;
    ml.b.y = m_y+m_h;
    for (x=start; x<end; x+=(MAPBLOCKUNITS<<FRACBITS))
    {
        ml.a.x = x;
        ml.b.x = x;
        AM_drawMline(&ml, color);
    }

    // Figure out start of horizontal gridlines
    start = m_y;
    if ((start-bmaporgy)%(MAPBLOCKUNITS<<FRACBITS))
        start += (MAPBLOCKUNITS<<FRACBITS)
                 - ((start-bmaporgy)%(MAPBLOCKUNITS<<FRACBITS));
    end = m_y + m_h;

    // draw horizontal gridlines
    ml.a.x = m_x;
    ml.b.x = m_x + m_w;
    for (y=start; y<end; y+=(MAPBLOCKUNITS<<FRACBITS))
    {
        ml.a.y = y;
        ml.b.y = y;
        AM_drawMline(&ml, color);
    }

}

//
// Determines visible lines, draws them.
// This is LineDef based, not LineSeg based.
//
void AM_drawWalls(void)
{
    int i;
    static mline_t l;

    for (i=0; i<numlines; i++)
    {
        l.a.x = lines[i].v1->x;
        l.a.y = lines[i].v1->y;
        l.b.x = lines[i].v2->x;
        l.b.y = lines[i].v2->y;
        if (cheating || (lines[i].flags & ML_MAPPED))
        {
            if ((lines[i].flags & LINE_NEVERSEE) && !cheating)
                continue;
            if (!lines[i].backsector)
            {
                AM_drawMline(&l, WALLCOLORS+lightlev);
            }
            else
            {
                if (lines[i].special == 39)
                {   // teleporters
                    AM_drawMline(&l, WALLCOLORS+WALLRANGE/2);
                }
                else if (lines[i].flags & ML_SECRET) // secret door
                {
                    if (cheating) AM_drawMline(&l, SECRETWALLCOLORS + lightlev);
                    else AM_drawMline(&l, WALLCOLORS+lightlev);
                }
                else if (lines[i].backsector->floorheight
                         != lines[i].frontsector->floorheight) {
                    AM_drawMline(&l, FDWALLCOLORS + lightlev); // floor level change
                }
                else if (lines[i].backsector->ceilingheight
                         != lines[i].frontsector->ceilingheight) {
                    AM_drawMline(&l, CDWALLCOLORS+lightlev); // ceiling level change
                }
                else if (cheating) {
                    AM_drawMline(&l, TSWALLCOLORS+lightlev);
                }
            }
        }
        else if (plr->powers[pw_allmap])
        {
            if (!(lines[i].flags & LINE_NEVERSEE)) AM_drawMline(&l, GRAYS+3);
        }
    }
}


//
// Rotation in 2D.
// Used to rotate player arrow line character.
//
void
AM_rotate
( fixed_t*		x,
  fixed_t*		y,
  angle_t		a )
{
    fixed_t tmpx;

    tmpx =
        FixedMul(*x,finecosine[a>>ANGLETOFINESHIFT])
        - FixedMul(*y,finesine[a>>ANGLETOFINESHIFT]);

    *y	 =
        FixedMul(*x,finesine[a>>ANGLETOFINESHIFT])
        + FixedMul(*y,finecosine[a>>ANGLETOFINESHIFT]);

    *x = tmpx;
}

void
AM_drawLineCharacter
( mline_t*		lineguy,
  int			lineguylines,
  fixed_t		scale,
  angle_t		angle,
  int			color,
  fixed_t		x,
  fixed_t		y )
{
    int			i;
    mline_t		l;

    for (i=0; i<lineguylines; i++)
    {
        l.a.x = lineguy[i].a.x;
        l.a.y = lineguy[i].a.y;

        if (scale)
        {
            l.a.x = FixedMul(scale, l.a.x);
            l.a.y = FixedMul(scale, l.a.y);
        }

        if (angle)
            AM_rotate(&l.a.x, &l.a.y, angle);

        l.a.x += x;
        l.a.y += y;

        l.b.x = lineguy[i].b.x;
        l.b.y = lineguy[i].b.y;

        if (scale)
        {
            l.b.x = FixedMul(scale, l.b.x);
            l.b.y = FixedMul(scale, l.b.y);
        }

        if (angle)
            AM_rotate(&l.b.x, &l.b.y, angle);

        l.b.x += x;
        l.b.y += y;

        AM_drawMline(&l, color);
    }
}

void AM_drawPlayers(void)
{
    int			i;
    player_t*	p;
    static int	their_colors[] = { GREENS, GRAYS, BROWNS, REDS };
    int			their_color = -1;
    int			color;

    if (!netgame)
    {
        if (cheating)
            AM_drawLineCharacter
            (cheat_player_arrow, NUMCHEATPLYRLINES, 0,
             plr->mo->angle, WHITE, plr->mo->x, plr->mo->y);
        else
            AM_drawLineCharacter
            (player_arrow, NUMPLYRLINES, 0, plr->mo->angle,
             WHITE, plr->mo->x, plr->mo->y);
        return;
    }

    for (i=0; i<MAXPLAYERS; i++)
    {
        their_color++;
        p = &players[i];

        if ( (deathmatch && !singledemo) && p != plr)
            continue;

        if (!playeringame[i])
            continue;

        if (p->powers[pw_invisibility])
            color = 246; // *close* to black
        else
            color = their_colors[their_color];

        AM_drawLineCharacter
        (player_arrow, NUMPLYRLINES, 0, p->mo->angle,
         color, p->mo->x, p->mo->y);
    }

}

void
AM_drawThings
( int	colors,
  int	colorrange)
{
    int			i;
    mobj_t*		t;

    for (i=0; i<numsectors; i++)
    {
        t = sectors[i].thinglist;
        while (t)
        {
            AM_drawLineCharacter
            (thintriangle_guy, NUMTHINTRIANGLEGUYLINES,
             16<<FRACBITS, t->angle, colors+lightlev, t->x, t->y);
            t = t->snext;
        }
    }
}

void AM_drawMarks(void)
{
    int i, fx, fy, w, h;

    for (i=0; i<AM_NUMMARKPOINTS; i++)
    {
        if (markpoints[i].x != -1)
        {
            //		w = SHORT(marknums[i]->width);
            //		h = SHORT(marknums[i]->height);
            w = 5; // because something's wrong with the wad, i guess
            h = 6; // because something's wrong with the wad, i guess
            fx = CXMTOF(markpoints[i].x);
            fy = CYMTOF(markpoints[i].y);
            if (fx >= f_x && fx <= f_w - w && fy >= f_y && fy <= f_h - h)
                V_DrawPatch(fx, fy, FB, marknums[i]);
        }
    }

}

void AM_drawCrosshair(int color)
{
    fb[(f_w*(f_h+1))/2] = color; // single point for now

}

void AM_Drawer (void)
{
    if (!automapactive) return;

    AM_clearFB(BACKGROUND);
    if (grid)
        AM_drawGrid(GRIDCOLORS);
    AM_drawWalls();
    AM_drawPlayers();
    if (cheating==2)
        AM_drawThings(THINGCOLORS, THINGRANGE);
    AM_drawCrosshair(XHAIRCOLORS);

    AM_drawMarks();

    V_MarkRect(f_x, f_y, f_w, f_h);

}
